The invention relates in general to gas-fired radiant burners, and in particular to an improved design for an infrared radiant burner of the type disclosed in U.S. Pat. No. 4,354,823, owned by the assignee of the present invention and incorporated herein in its entirety by reference.
U.S. Pat. No. 4,354,823 discloses a single-wall sheet metal box functioning as a gas plenum. The box has an open face closed by a porous, gas-permeable matrix of refractory fibers bonded together to form a rigid, boardlike heating element. A combustible gas mixture is fed into the box, forced through the porous heating element, and burned at the outer face thereof to provide a continuous infrared radiant surface.
The outer surface of the sheet metal box is completely covered by a blanket of flexible insulation material having an edge portion stuffed between the periphery of the heating element and an adjacent flange-like edge of the box.
A first type of snap-on clip maintains the heating element in position, while a second type of snap-on clip retains the stuffed edge of the insulation blanket between the heating element periphery and the adjacent edge of the box.
While the foregoing prior art radiant burner represents a substantial advance in the art, it is still rather complex and costly from both a materials and manufacturing standpoint.
For example, the use of numerous clips to maintain the heating element and insulation blanket in position on the plenum box requires a fairly complex manufacturing sequence.
Also, the nonwoven insulation blanket disclosed in the noted prior art patent has been found to be susceptible to damage. For example, the blanket can easily be torn during initial installation of the burner.
Accordingly, it is a primary aim of the present invention to provide a gas-fired radiant burner which overcomes each of the aforementioned shortcomings without offsetting disadvantages.